Milk refrigerating cabinet



April 1937- W. F BORGERD ET AL 2,077,871

MILK REFRIGERATING CABINET 5 Sheet-Sheet 2 Filed Dec. 29, 1934.

April 20, 1937. W. F. BORGERD ET AL 2, 1 I

MILK REFRIGERATING CABINET Filed Dec. 29, 1954 5 Sheets-Sheet 5 April1937. w. F. B-ORGERD ET AL 2,077,871 v 7 MILK REFRIGERAT ING CABINETFiled Dec. 29, 1934 5 Sheets-Sheet 4 April 20,, 1937. wxF. BORGERD ET ALMILK REFRIGERATING CABII IET Filed Dec. 29, 1934 5 Sheets-Sheet 5Patented ApnZO, 1937 a V} UNITED STATES 2,077,871 M nx amonna'rmacssnm'r William F. Borgerd, Riverside, and m L. m-

Cune and Charles A. Uh'erek, Ohloagoplllg, alv signors to Internationalcorporation of New Jersey Harvester Company, a

. Application December 29, 1934,- saw no. traces 8 Claims; (01. s -101)This invention relates to a cooling "device.- More specifically, itrelates to a milk cooling device including a cabinet, a refrigeratingunit, and

means cooperating with .the unit andthe cabinet to facilitate the heatexchange;

In the handling of .milk, it is very desirable to cool the milkquickly'to a temperature below that at whichimportantlbacterial actiontakes place, in order to improve the keeping 'quality and" flavor of themilk: This step in the handling of milk is so desirable thatr-in somemilk producing areas laws have been made requiring the cooling of milkto a certain specified temperature within an hour's time after milking.The milk is 1:.- usually placed. in cans, after being preliminarilycooled, and then placed in liquid tanks to complete the cooling. Thereis a relatively large amount of heat in cans of milk of this-size, andthe rate of heat transfer is not rapid unless some form of agitation isresorted to, or unless a comparatively large heat differential is main-.tained. As the cooling is often done on a smallfarm, it is usuallynecessary to produce the refrigeration in a unit particularly designedfor a milk cooler. By calculating the total amount of B. t. u.s to beremoved from the milk-in thegiven length of time, the amount ofrefrigeration and the size of unit required can readily be determined.It is obvious that, if the refrigeration is to be done in a very shortlength of time, a large unit is required. v

It is to solve some of the above problems in a commercially feasiblemanner that the present milk cooling device has been designed andconstructed. v

The principal object of the present invention is to construct andoperate a milk cooling device utilizing a comparatively smallrefrigerating unit, yet being capable of extracting a large amount-ofheat over a short period of time. A more specific part of this object isto provide a refrigerating unit capable of building up an ice bank ofaccumulated refrigeration during a stand-by period of operation, and toprovide means for rapidly transferring heat from the container tobecooled to the ice bank.

Another object is to provide in a cooling device a novel means ofpnuematic agitation. A more speciilcphase of this object is to providean air circulating pump operable for supp y ng air for a predeterminedperiod of time.

Another object is the provision of an air pump particularly adapted tocirculate air to a cooling device. a

The above deflnedobjects and others, which will be apparent from the,detailed description to follow, are obtained by a milk cooling tank anda refrigerating unit. and certain novel construction and arrangement ofparts associated there- I '60 with. The refrigerating coils have beenarrefrigerating unit.

ranged in the tank spaced from the wallsthereof to form an ice bankduring stand-by operation ofrthe machinev when the refrigerating loadissmall. A perforatedxpipe'including in some cases a particular type ofhome for directing the air jets is arranged at :the bottom ,of the tank,to

provide a current of air for sweeping the walls of the-icebank,'preventing the insulating effect.

of a stagnant liquid film adiacent'the ice. To provide an 'air supplyfora predetermined length of time, a par icular type of airpump, old in theart but new in an application of this type, is

drivenv directly off the compressor motorof the The pump'is of a:rotating vane, liquid seal type. Theconstruction of the pump has beenworked out in such a mannerthat the amount of time required to atomizeand otherwise entrain a certain amount of liquldis a known factor. Itis, therefore,evident that. by placing a certain amount ofliquid in the"pump, it will operate for a given length of time. The liquid seal isthen broken and the pump merely rotates without any air forcing action.

A device constructedto incorporate the features I of the invention andtoattain the objects above set forth is shown in the drawings. in which:

Figure 1 is a top plan view of a milk cooling cabinet with arefrigerating unit mounted atone end, the top of the cabinetbeing brokenaway at the other end to show theinterior thereof and the constructionof the insulating wall; 1

Figure. 2 is a vertical, longitudinal section of the device as shown inFigure 1',v with the refrlgerating unit shown in side elevation? Figure3 is anend .elevation'of the air circu lating pump shown as a part ofthe refrigerating unitinFlguresland.2;-. v Figure 4 is a section takenon the line H of Figure 3, the compressor motor to which the air 1 pumpis connected being shown in side elevation; Figure 5 is an end elevationof the inside of the pump housing cover plate;

I Figure 6 is an and elevation of the insideof the pump housing;

Figure 7 1s an end elevation of the outer end of the pump impeller;

- Figure 8 is an end elevation of thepump inlet and outlet plate fromtheinner side thereof Figure 9 is an end elevation of the pump inlet andoutlet plate taken from the outer side; and,.

Figure 10 is a. bottom plan viewof the plate shown in Figures 8 and 9. vThe milk cabinet used in this device may. be of any conventionalconstruction. As shown, the cabinet I0 is constructed of a wall I I ofinsulating blocks, an-outer metalcasing lhand an inner, metal lining l3Angle bars M along the bottom of the cabinet. form fsupporting meanstherefor. Itwill be'noted that at the top of the casing, outer anglebars I! and inner angle bars I! around the cover opening have theiradjacent top edges spaced apart to provide a non-metallic insulatingsection. to minimize the conduction of heat. A cover l1 encased in metalis hinged to the top 5 of the casing. It is to be understood that thebest insulating construction obtainable is used for cabinets of thistype.

A continuous refrigerating coil I6 is arranged around the tank inslightly spaced relation from 10 the walls and with the upper coil at alevel normally below the level of the liquid in the tank when itcontains no cans. The adjacent turns of said coil are positionedvertically above each other and the complete coil is held in position bya plurality of vertical standards I3, to which the turns of the coil aresecured in any suitable manner. One end of the coil connects with aconduit 26 connected with acondenser 2| of the refrigerating unit. Theother end of the coil connects with a conduit 22 leading to the intakeof the cylinder of a compressor 23. A conduit 24 leading from thecompressor to the condenser 2| completes the refrigeration cycle. Theseelements and other elements, such asv expansion valves and the like, 25making up a refrigeration cycle of this type, have not been illustratedand described, as they may be.

conventional in' construction, as well known in the The compressor 23 isa part of a refrigerating unit mounted on a base 25 positioned on top ofthe cabinet II) :at one end thereof. Said compressor is driven by anelectric motor 26.

At one end of the motor 26, a pump housing 21 is rigidly secured by'aplurality of integral extensions 28 bolted tothe motor frame. The pumphousing 21 is formed. as a casting cored out to accommodate a pumpimpeller 26 and other passages forming the pump unit.

The impeller 29, as shown in Figure 7, is provided with a center portion36 formed with an axial bore bywhich the impeller is secured on anextension 31 of the motor shaft. Said shaft extends through an opening32 in the pump housing without contacting the housing. A sealing memher33, formed with'an annular channel to prevent the escape ofliquid, ismounted on the housing wall within the housing around the shaft 3| outof contact therewith. A cup-shaped member 34 secured co-axially with theimpeller 26 around the shaft 3| extends in overlapping relation withrespect to the sealing member 33 and is provided with an outwardlyextending flange tothrow liquid outwardly into a receiving chamberformed by a flanged member 36 fitted in an annular re- 5 cess formed inthe housing wall. From the chamber formed by this member liquid drainsthrough a conduit 36 into a nozzle member 31, which functions as will behereinafter described. The impeller23' around the central portion 36 isprovided with a plurality of vanes 36 shaped to effectively form an: airpump in the-particular construction in which it is incorporated; At oneend, the. impeller is provided with an annular flange 39 sealing thespace between the vanes and forming thereby compartments in combinationwith the retaining wall at the other end of the vanes, to be hereinafterdescribed.

An inwardly projecting. flange 40 terminates in alignment with aninwardly directing flange 4| formed on the housing wall to cooperativelyform a part of the liquid seal. The outer side of the flange, or wall,39 is provided with a series of annular ridges 42, which cooperate inmating relation with a plurality. of similar ridges 43 onv the housingwall to forms labyrinth sealing passage ever, of a pump of this natureand of its mode of operation, the Nash Patent No. 1,091,529, March 31,1914, is referred to. Figure 7 of this patent shows a two-compartmentpump very similar in 15 its general construction to that shown andherein described. 7

As best shown in Figure 6, a crescent-shaped water compartment 46 isformed around the upperside of the pump housing 21 above the im- 20peller compartment. A- filling plug 46 provides means for filling thecompartment with liquid to the desiredlevel.

A plate'41, having the same outside shape as the housing'21, is fittedover the open face of said 25 housing opposite the end wall. As shown inFigures 8 and 9, said plate is provided with a plurality of recessesforming conduits in combination with the housing 21 and the cover plate-48, which isfltted over the plate 41, suitable 3 gaskets being utilizedbetween the-cover plate and the plate 41 and between the plate '41 andthe housing 21. The plate 41 is provided at its bottom edge with an airintake conduit 49 provided with an oriflce .49 used for starting, aswill be hereinafter described. The conduit 43 communicates with arecess, forming a conduit 60. Said conduit communicates through anopening 6| through the plate with the impeller adjacent the centralportion 30 and through a second opening 40 62 with the impeller at adiametrically located point. The openings 6| and 62 are Joined byrecesses formed in the plate 41. An outlet conduit 63 at the lower edgeof the plate 41 communicates by means of a conduit 64 formed by a 45recess in the plate. 41 with an opening 66 extending through the plate.Said opening places the conduit 64in communication with the compartment46 in the top of the pump housing. It will-be noted that the opening 56is at the upper- 50 most point in said compartment. An opening 66,somewhat lower vertically than the opening 66, forms a means ofcommunication between the compartment 46 and branch conduits 61 formedby recesses in the plate 41. Said conduits, which 5 form the means fordischarging air from the pump chamber, communicate therewith throughdiametrically positioned openings 66.

The-nozzle member 31, previously described as conducting water from theliquid seal, extends 60 into the inlet conduit 60, being formed with anend portion to produce somewhat of a suction effect, whereby liquiddelivered therefrom is entrained with the air and is drained into theinlet side of the pump impeller. An opening 66 formed at the lowermostpoint of the impeller chamber communicates also with the conduit 36,whereby liquid draining therefrom passes through the nozzle member 31.During normal operation of the pump, the liquid escaping through theopen- "0 ing 66 is entrained in the air stream and returned to the pumpchamber. i

l A conduit 66 formed by a recess in the plate 41 communicates throughan opening 6| with the lowermost point in the liquid chamber 46 at oneside thereof. Said conduit delivers the liquid back into the inletpassageill. Avalve 62, extending outwardly through the cover plate 48,provides means for regulating the flow of liquid through the conduit 60.v I I I A conduit 63, formed by a recess in the cover plate 48,communicates through an opening, extending through the plate '41 withthe water chamber 45 at the end opposite the communication of theconduit 60. At its other end the conduit 63 communicates with theconduit 60 ahead of the orifice 62, whereby said orifice regulates theflow of liquid from both ends of the compartment45.

The outlet conduit 53 of the air pump-is connected with a conduit 65leading to a perforated pipe 66 placed around the bottom of the cabinetI0. Said perforated coil is positioned inwardly a substantial distancefrom the refrigeratingcoil ill, the perforations being on the side ofthe coil adjacent the refrigerating coil. Bailie members 61 have endportions radiallybent around the pipe 66 and a deflecting flangeextending up,- wardly and outwardly toward the refrigerating coil Ill.The flanges of said members may be corrugated to assure distribution ofthe air lengthwise of the flange. The length andpositioning of theflanged portion of said members i depend upon the spacing of the coil 66from the refrigerating coil l8 and upon the nature of the ice bankformed around therefrigerating coil in a normal condition of operation.An ice bank,

has been indicated at the ends of the cabinet in Figure 2 to illustratethe functioning of the device. The liquid level has also been indicatedat the top of its normal level, said liquid not being otherwiseindicated because of its confusing effect upon the drawings.

In the operation of a device as above described, 40 the refrigeratingunit is provided with the conventional automatic controls as used inhousehold refrigeration. During stand-by operation, the controls for themachine, which are not shown in this application, are regulated so thatan ice bank of predetermined thickness is formed around therefrigerating coil l8 before the refrigeration is cut off. There is noliquid in the pipe during this period of operation, and the impellerrotates freely thereirr with no friction except the very slight-amountof air drag upon the impeller.

When milk cans are put into the cabinet, this being shown in theillustrated form ,the temperature of the liquid immediately rises andthe refrigerating unit is operated at full capacity. With a small unitof an economical size, a conslderable period of time, much in excess ofthe desired time, would be required to extract suflicient heat from thecans of milk to reduce the temperature to the desired point. J, However,in addition to the refrigerating capacity of the unit,

refrigeration has been stored up, so to speak, in the ice bank. Theproblem, then, is to rapidly transfer the heatfrom the cans to the icebank to obtain the latent heat required in melting the ice.

, When the milk cans are placed in the cabinet, the cock 49' is closedand liquid is poured into the chamber 45, filling said chamber up to thefiller opening. In the commercial embodiment of this device, the chamber45 is constructed of such a size as to contain suiiicient liquid for thedesired period of operation,generally about one hour. The liquid flllsthe impeller chamber and seals the ends of the impeller vanes betweenthe .75 vanes and the chamber. The cock 49' is then A certain amount,however, passes on with the air throughthe outlet conduit 53 into theperforated coil 66.

Air discharged from the perforated coil 66 is delivered over the ballles61 alongthe surface of the ice bank. The air carries along the liquidwith it, sweeping the walls of the ice bank, and rapidly melting theice. The cool liquid circulates around thecans and down to the bottom ofthe cabinet. In this manner the bubbling air not onlyv removestheinsulatinglayer. of warm water from the surface of theme, but alsomaintains a circulation around the cans. It has been found that an icebank of substantial thickness can be melted in about'an hour's time andthat'the milk in the cans can be cooled to the desired temperature inthe same length of time. h 3 I,

The liquid in the pump chamber isgradually depleted, as' abovedescribed. After a certain amount of liquid has been removed in thecourse of operation, the liquid seal is broken between the ends ofthevanes and the pump chamber. As soon as this happens, even in anirregular manner, the inlet suction is reduced. Water normally entrainedfrom the nozzle member 31 flows downwardly through the air intake intothe tank. The

escape of liquidffrom the pump chamber through the opening 5 9 hastensthe unsealing action'fonce it has started, and completely. breaks theseal after a short period of such an irregular type of operation. Liquidfrom the chamber 45 drains through the conduit '60 into the inletconduit 50 and back into the cooling cabinet, and through the conduit65. The liquidalso drains from the pump chamber, as previouslydescribed. The impeller is then free to rotate without any appreciablefriction and continues in operation whenever the motor is in operation,without, however, the pumping of anyair to the perforated coil 66.

It will be understood, as above described,that the cooling device asconstructed is substantially automatic in operation to rapidly cool to apredetermined temperature within a short period of time and tosubsequently supply refrigeration at a normal rate. Also the device iseffective during stand-by periods of operation, when incorporated .withconventional controlling mechanisms, to

store up accumulated refrigeration in the form of an ice bank forvperformingsubsequently its rapid cooling operation. By such aconstruction and by its operation as above set forth, a small-capacityrefrigerating unit is efiective to accomplishfor a short time a heavyrefrigeration Job. Another important feature of the invention is thefreedom from agitating means in the milk itself, whichis alwaysundesirable, and the provision of agitating means free from wearingparts and substantiallyautomatic in operation.

It is who understood that applicant has shown and described only apreferred embodiment of his novel cooling device and means foritsoperation,

' and that he claims as his invention all modifications fallingwithinthescope of the appended claims. v

Whatisclaimedis:

1. A cooling device for cooling material at a rapid rate comprising awater tank, cooling coils positioned in said tank, means for supplying arefrigerant to said coils during a stand-by'period of 5 operation withheat removing capacity in excess of the heat transferred thereto wherebyice is formed rapid rate comprising a tank for. containing water,

refrigerating coils positioned in said tank, a refrigerating device forsupplying a cooling medium to said coils for forming ice therearoundduring one period of operation, a perforated air supply pipepositionedin'the tank to agitate the water adjacent the ice around thecoils during a period of rapid cooling of material in the tank, andmeans for supplying air to said pipe during said period, said meansbeing associated with means to automatically discontinue the supply ofair after a predetermined period of rapid cooling.

-3. A cooling device comprising a tank for contank, a refrigeratingdevice for supplying a cooling medium to said coils for forming icetherearound, a perforated air supply pipe positioned in the tank toagitate the wateradjacent the coils, and means for supplyi g air tosaidpipe for a predetermined period, said means being operable toautomatically cease to supply air after said period. 4. A cooling devicecomprising a tank for containing water, refrigerating coils positionedin said 40 tank, a refrigerating device for supplying a cooling mediumto said coils for-forming icetherearound, a perforated air' supply pipepositioned in the tank to agitate the water adjacent the coils, meansfor supplying air-to said pipe for a predetermined period consisting ofa casing having an eccentric chamber therein, an impeller mounted insaid i chamber, air inlet andoutlet means to said chamber, means tosupply liquid to the chamber to seal the impeller with respect to thecasing, said chamber being formed to hold'a given quantity of liquid,

said quantity being predetermined to give a predetermined period of opration prior to its being depleted, by evaporation and entrained by theair stream,'and1means to drain the liquid from'the 5 casing when theseal is broken by depletion of the liquid.

5. A cooling device which comprises a water receptacle. means forsupplying a cooling medium in heat exchange relationship with saidwater, said vmeans being effective to solidify a portion of the water atcertain periods of operation whereby. extra refrigeration is obtainedfor a subsequent period of operation, means for agitating the wateradjacent the solidified portion for a given'period of time during saidsubsequent period of operation 1 to increase therate of heat transfer,and means for automatically stopping the agitation after a predeterminedperiod of rapid cooling.

' 6. A cooling device'comprising a tank forcon-j 6 taining water,refrigerating. coils positioned around said tankin substantiallyvertical planes, means for supplying a cooling'medium to said coils,said means having sufficient capacityto form taining water,refrigerating coils positioned in said a bank of iceon the coiisduring astand-by period of operation, perforated air supply pipes locatedadjacent the bottomof the tank substantially beneath "the areas in whichthe ice banks are formed, a pump forsupplying air'under pressure to saidpipes consisting of a casing having an eccentric -.chamber therein, arotatable impeller mounted in said chamber, a shaft extending fromtheimpeller through one wall of the casing, an

air inlet to one area of the face of the impeller,

and an air outlet from another portion of the face of the impeller, saidoutlet connecting with the air supply pipes in the tank, and means forsupplying liquid to said casing for sealing the space between theimpeller and the surrounding tank in substantially vertical planes, acompressor expander refrigerating device for supplying a cooling mediumto said coils, said device having sufflcien't capacityto form a bank ofice on the coilsduring a stand-by period of operation, perforated airsupply pipes located adjacent the bottom of the tank substantiallybeneath the areas in which the ice banks; are formed, means forsupplying air under pressure to said pipes, said means consisting of anair pump driven by the same source of power as the refrigerating device,said pump consisting of acasing having an eccentric chamber therein, arotatable impeller mounted in said chamber, a shaft extending from theimpeller through one wall of the casing, a labyrinth oillessseal-between the shaft and the casing wall, an air inlet to one area ofthe face of the impeller, an

[air outlet from another portion of the face of the impeller, saidoutlet connecting with the air supply pipes in the tank and saidinlet'connecting with the tank above the liquid,level therein,

means for supplying liquid'to said casing for sealing the space betweenthe impeller and the surrounding compartment whereby air circulation isobtained, said chamber-being formed to hold a quantity of liquidpredetermined by the loss due to agitation and evaporation to obtain apredetermined time period of operation of the pump, and means fordraining the residual liquid from the pump into the tank when-the sealis broken by depletion ofthe liquid.

8.. A cooling device comprising a tank for containing water, coolingcoils positioned in said tank below' the normal liquid level, means forpassing a cooling medium through said coils suillcient to form an' icebank there-around during certain periods'of operation, 'and'means forincreasing the rate of heat transfer to the liquid during subsequentperiods of, operation including means for supplying, agitating gasesbeneath the liquid. level adjacent the ice bank, said means comprising aperforated pipe positioned below the ice bank and a deflector looselypivoted adjacent the pipe and terminating beneath the ice I wnmsrr'.nondnnn. FRED L. McCUNE. cmnms a ummnx.

